John Deere Generator: Water Level Low

[greenmojo]

Hey all;

That JD generator up here on the property (30,000 watt Katolight) is alarming with Water Level Low... however, radiator is full, and reservoir is filled about half way.

I clear the alarm, try to start and it cranks once or twice then shuts off with the same alarm.

Any ideas? I'm not even sure where to look.

Anything would be much appreciated.

~Moses

 

[Bladehauler]

I don't know about your generator , but most heavy equipment will have a sensor in the top tank of the radiator, can be replaced with out losing too much coolant if your quick.just look for a pair of wires going to the top tank of the radiator and you've probably found it .

 

[greenmojo]

I saw a sensor on the top left side, I'll grab numbers off of it and start making calls.

I really appreciate it.

As a side question, what is the purpose of the overflow coolant tank. Of course, other than overflow, does it have some magical ability to be siphoned back up into the radiator? Or am I just over thinking that thing.

 

[doxford jim]

Just a shot in the dark, but what condition is the radiator cap in ? If the spring is weak and allows warm water to exit, it could be the reason for using the cooling water.
While you are in the buying mood, buy a new radiator cap - it might help and also would not be too expensive. Just replace the old cap and wait and see what happens.

 

[Bladehauler]

I saw a sensor on the top left side, I'll grab numbers off of it and start making calls.

I really appreciate it.

As a side question, what is the purpose of the overflow coolant tank. Of course, other than overflow, does it have some magical ability to be siphoned back up into the radiator? Or am I just over thinking that thing.

yep , as coolant heats , it expands building pressure, the radiator cap has a spring that will keep the cooling system at a specified pressure, ( 15psi ) over the preset pressure, the cap will bypass coolant to the overflow tank . When the system cools down, the radiator cap will allow coolant to siphon back to the radiator through its 1 way valve ( the metal disk surrounded by the rubber gasket when looking at the radiator side of the cap ).
gen-sets are run without anyone keeping an eye on the gauges, so the low coolant shutdown system is necessary in case of a catastrophic failure ( blown coolant hose ) it will save that engine from a total meltdown.

Hope this helps,
Scott

 

[greenmojo]

Just a shot in the dark, but what condition is the radiator cap in ? If the spring is weak and allows warm water to exit, it could be the reason for using the cooling water.
While you are in the buying mood, buy a new radiator cap - it might help and also would not be too expensive. Just replace the old cap and wait and see what happens.

It's the original cap, 7 or 8 years old and appears to be in good condition. But regardless I'll take your advice and grab another one.

I'm learning and had no clue that a radiator cap was anything more than a "cap".

yep , as coolant heats , it expands building pressure, the radiator cap has a spring that will keep the cooling system at a specified pressure, ( 15psi ) over the preset pressure, the cap will bypass coolant to the overflow tank . When the system cools down, the radiator cap will allow coolant to siphon back to the radiator through its 1 way valve ( the metal disk surrounded by the rubber gasket when looking at the radiator side of the cap ).
gen-sets are run without anyone keeping an eye on the gauges, so the low coolant shutdown system is necessary in case of a catastrophic failure ( blown coolant hose ) it will save that engine from a total meltdown.

Hope this helps,
Scott

That helps significantly. I didn't know the cap was as sophisticated, I was staring at that overflow tank last night wondering how it was able to get fluid back up inside. Now I know.

I appreciate all of the info. I'll get the sensor and cap replaced and report back.

~Moses

 

[greenmojo]

Any recommendations on where to get a new sensor, local JD said it's an aftermarket sensor and is sending me to an auto parts store.

?

~Moses

 

[Bladehauler]

Any heavy truck dealer Peterbilt Kenworth Freightliner should be able to help you .
Almost all heavy trucks have the same sensor in the radiator to protect from coolant loss

Just tell them what you're working on hand them the sensor and ask them to help you , they should be able to match it up pretty easy

Good luck !!!
Scott

 

[greenmojo]

Perfect, I found a local dealer who knew what it was and ordered me one.

Thank again everyone, another problem solved!